Now being a real numpty in the tuning dpt. Could someone fit one of your racier cams into a standard C11 and get much improvement in the running/power or would you need to do the porting & flywheel balancing as well to achieve a significant power gain e.g. +2Hp?

hi owenmaking these cams up is very labour intensive and needs a high compression ratio, but there are other things you might want to do first.here is a list of what i think would help :-cut off the perforated end of the exhaust pipe and use a burgess type silencer, or an open pipe ending at the rear spindle, it is not too loud - probably need to go up a jet size.the inlet length is far too short - you could make an angled flanged spacer between the carb and head.the inlet port could be opened out a size and the port and valve fettled then go up a size in carb diam.i have seen the imp piston used but you could very easily spoil a barrel by breaking through at 68mm.i have used the 66mm wiseco honda k4 piston - you would need to make a small end bush and skim a bit off the barrel. (bore it nice and slack to avoid nipping).make a head gasket with 0.9mm annealed copper.all that can be done without taking the engine out and make a noticable difference in performance.then you could machine the flywheels a bit which would help with throttle response and acceleration in the lower gears.then fit a racier camcheers bill

hi folksstill messing with the c11 on the rolling road dyno (it's a great thing - on a 10 second run say you can glean all the info immediately after on the lap top with graphs and reports and everything in between - intake temperature, cylinder head temp. exhaust gas temp. air fuel mixture ratio, revs, horsepower and torque)on the first engine with the standard crank and honda piston- 273cc i have squeezed 21hp at 6250 revs, now i am in the process of testing the second engine with the short stroke crank and big beefy big end and home made rod with honda piston 248cc and i am up to 19.5hp at 6750 revs with the rev limiter set at 7500 revs - i have still got more things to tryi have just ordered 20l of methanol to get a back to back test against 95 octane petrol, if it is good i have a high comp. piston to try (about 12.5:1).based on my experience out on the road with the first racer i am in the process of building another with a whole lot of refinements - there should be photos attached.

my arthritis has got me pretty fckud, but next week i am getting my right hip done and as soon as i can after get my left one done then hopefully i will be able get my leg over the saddle and if that all works i would like to get a semi modern v twin, but i have no idea what to look for -- i am open to suggestions.cheers again bill

Very interesting, Billy! In the last pic, i see you've modified the gearbox plates as well. Next to the plates, what are the two steel bars for? That bolt in the middle, is it your "memory" for adjusting primary chain?Wish you all the best with your hips and good recovery! Paul

hi paulas the joint at the rear of the gearbox plates is probably the weakest and wobbliest part of the bike but is critical to stability of frame and rear chain tension i have tried to beef it up as much as i can.the side plates are to put that part in a double shear, i have also welded a strip of flat bar along the length of the underside of the drive side gearbox plate.the whole mod. has very effectively strengthened and stiffened up assembly.there should be some close ups to help explain.cheers bill